Safe and sound in a breeding cage I have the chrysalids of five rescued large white butterflies.

Eggs were laid in mid-September, quite late in the season and after feasting on nasturtium, the caterpillars pupated in early October.

Because they pupated so late the butterflies wont emerge until next spring so entered a period of suspended animation (diapause) for although the weather was quite mild, daylight hours are crucial and if insufficient, the butterflies would be unlikely to find nectar to survive and the species does not hibernate in the adult stage.

This is nature's way of ensuring that if by some freak accident large whites all died out in the autumn, then those emerging next spring will be able to guarantee survival of the species. I will release them at that time when they hatch in March or April.

A similar strategy occurs with bush crickets. Eggs are laid into the bases of grasses and plants in summer. Most will hatch the following year but a proportion delay hatching for two years which is a safeguard in case the crickets are faced with a poor breeding season.

Nature needs a helping hand to stem the ongoing dramatic decline in our insect populations caused mainly by harmful pesticides and habitat loss.

Flying insects including bees are especially at risk and are essential major pollinators of our food crops so their decline is extremely worrying. The picture shows a large white butterfly.